[Sajid Sarfraz]

Hi

This is Sajid

I am presently working on Vortex Induced Vibrations of Circular Cylinder in ANSYS Fluent

I have already completed 2D Case of VIV (Cross Flow Direction Only) using following UDF.


#include "udf.h"

static real v_prev_y = 0.0;

DEFINE_CG_MOTION(viv,dt,vel,omega,time,dtime)
{

Thread *t;

Domain *d;

FILE *fp;

real cg[3], force[3], moment[3];

real accl_y, dv_y;

real ured=6.02;

real mass_ratio = 149.10;

real eta = 0.0012;

real ro = 1.225;

real wn_y = (2*M_PI)/ured;

real mass = (ro*M_PI*mass_ratio)/4;

real k_y = mass*wn_y*wn_y;

real c_y = 2*mass*wn_y*eta;

int i;

NV_S(vel,=,0.0);

NV_S(omega,=,0.0);

t = DT_THREAD(dt);

d = Get_Domain(1);

for(i=0;i<3;i++)

cg[i] = DT_CG(dt)[i];

Compute_Force_And_Moment(d, t, cg, force, moment, TRUE);

force[1] += -k_y*cg[1] - c_y*vel[1];

accl_y = force[1]/mass;

dv_y = accl_y*dtime;

v_prev_y += dv_y;


Now i want to simulate XY Motion i.e both Inline and Cross Flow direction in ANSYS Fluent.

Can anybody send me UDF of XY Motion ???

[n.mai]

Originally Posted by Sajid Sarfraz

Hi

This is Sajid

I am presently working on Vortex Induced Vibrations of Circular Cylinder in ANSYS Fluent

I have already completed 2D Case of VIV (Cross Flow Direction Only) using following UDF.


#include "udf.h"

static real v_prev_y = 0.0;

DEFINE_CG_MOTION(viv,dt,vel,omega,time,dtime)
{

Thread *t;

Domain *d;

FILE *fp;

real cg[3], force[3], moment[3];

real accl_y, dv_y;

real ured=6.02;

real mass_ratio = 149.10;

real eta = 0.0012;

real ro = 1.225;

real wn_y = (2*M_PI)/ured;

real mass = (ro*M_PI*mass_ratio)/4;

real k_y = mass*wn_y*wn_y;

real c_y = 2*mass*wn_y*eta;

int i;

NV_S(vel,=,0.0);

NV_S(omega,=,0.0);

t = DT_THREAD(dt);

d = Get_Domain(1);

for(i=0;i<3;i++)

cg[i] = DT_CG(dt)[i];

Compute_Force_And_Moment(d, t, cg, force, moment, TRUE);

force[1] += -k_y*cg[1] - c_y*vel[1];

accl_y = force[1]/mass;

dv_y = accl_y*dtime;

v_prev_y += dv_y;


Now i want to simulate XY Motion i.e both Inline and Cross Flow direction in ANSYS Fluent.

Can anybody send me UDF of XY Motion ???

Hi, may I know what is M_PI? is it for pai=3.142?

Thank you.

[AlexanderZ]

Originally Posted by n.mai

Hi, may I know what is M_PI? is it for pai=3.142?

Thank you.

yes

next time you may find information about macros in ansys fluent customization manual

[n.mai]

Hi Mr. Alexander Z,

Thank you for your information and guidelines. ����